Genome-wide identification of CsREMs and their roles in tea plant overwintering bud dormancy and sprouting.

The Reproductive Meristem (REM) family, a subfamily of the B3 gene family, plays important regulatory roles in plant reproductive development and stress responses. This gene family has not been comprehensively identified and genetically characterized in tea plants. This study identified 34 REM genes in tea plants, which are unevenly distributed across seven chromosomes. Phylogenetic analysis categorized the CsREM genes into four groups, all with B3 domains and promoters containing abiotic stress- and hormone-related cis-responsive elements. The genes displayed nuclear localization and tissue-specific expression patterns. In expression profile analyses, CsREMs were responsive to cold stress, drought stress, and anthrax infection, and exhibited differential expression at various developmental stages of seeds and flowers. Specifically, CsREM27 and CsREM31 exhibited expression patterns that align with bud dormancy and sprouting status; oligonucleotide silencing assays confirmed their involvement in regulating tea bud sprouting. Collectively, these findings provide valuable insights into the function of REM genes in controlling overwintering bud growth and development of tea plants.